Written by: Andrew Biemiller, Ontario Institute for Studies in Education, University of Toronto

At any age from 0 to 60 months, parents and caregivers should be alert to the possibility of hearing problems.
Both congenital (permanent) hearing problems and temporary hearing problems as a result of infections can affect
your child's language development. Warning signs include earaches, failure to respond to calls or loud sounds, or
inability to produce any words by 13 or 14 months. If you suspect a problem with your child's hearing, take
your child immediately to the public health nurse, a doctor, or pediatrician. When the problem is diagnosed,
recommendations for further help will be made, if needed.

It is difficult to assess language prior to two years of age. After two years of age, a psychologist or speech language
pathologist can make some assessment of receptive vocabulary (words understood), and normal development of speech. Often
some phonemes are not produced accurately until around four or five years of age. For example "r" sounds as in
rock and rude may be pronounced "wock" and "wude". If your child continues to mispronounce words
at age five, seek the help of a speech language pathologist.

Sometimes, preschool children make syntactic errors but these errors are often a good sign that they are using the general rules of
language and are progressing well. For example, some grammatical errors around ages two to four actually indicate
advancing language. Children, who have mastered the past tense, often "regularize" words. For example,
instead of "went", children might say "goed". Such errors usually self-correct
by second or third grade. They are a good sign of good language development.

Assessment of children's vocabulary development is quite feasible after two years of age. However, current methods
that use pictures are somewhat restricted to words that can be clearly pictured. Verbally-defined words (e.g.
fair, possible) are usually not assessed.

When should you seek assistance with vocabulary? I recommend on-going attention to your child's hearing (at least every year
as part of a pediatrician's check-up). Beyond that, if your child does not understand words and stories read to
them and do not seem to understand what most children of the same age understand, I would consult an early
childhood educator, the public health nurse, kindergarten teacher, psychologist or speech language pathologist.

Biemiller, A. (2009). Vocabulary Development 0 – 60 Months: Where And How To Get Help. In L.M. Phillips (Ed.),
Handbook of language and literacy development: A Roadmap from 0 – 60 Months. [online], p. 1. London, ON:
Canadian Language and Literacy Research Network.